Trouble with LJ Code

If I recently loaded Lj source code for my company to our server, will all of the code for the themes style sheets be loaded as well? If everything else appears to be running great but my themes are just showing up blank, what does this mean? I wanted to edit a certain style sheet so that my LJ would kind of have the same color scheme as my ppc management service website. I'm not even sure where to begin to attempt to fix this problem. By the way, any tips when editing the style sheet code would be appreciated. (I guess I need to get this problem fixed first)